"Those who fervently wish for car-free cities should take a closer look at New Orleans. The tragedy of New Orleans isn't primarily due to racism or government incompetence, though both played a role. The real cause is automobility -- or more precisely to the lack of it.
...The ... people who got out were those with automobiles. Those who stayed, regardless of color, were those who lacked autos.
What made New Orleans more vulnerable to catastrophe than most U.S. cities is its low rate of auto ownership. According to the 2000 Census, nearly a third of New Orleans households do not own an automobile. This compares to less than 10 percent nationwide. There are significant differences by race: 35 percent of black households but only 15 percent of white households do not own an auto. But in the end, it was auto ownership, not race, that made the difference between safety and disaster."
Thanks to Randal O'Toole